<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script type="text/javascript">
			let num = window.prompt("请输入一个数：");
			if (num > 100) {
				document.write(100);
			}else{
				document.write(num);
			}
			
		</script>
	</body>
</html>
